U.S. patent number 7,934,944 [Application Number 12/296,430] was granted by the patent office on 2011-05-03 for electrical connecting apparatus.
This patent grant is currently assigned to Kabushiki Kaisha Nihon Micronics. Invention is credited to Takashi Akiniwa, Kazuhito Hamada, Satoshi Narita.
United States Patent |
7,934,944 |
Hamada , et al. |
May 3, 2011 |
Electrical connecting apparatus
Abstract
An embodiment of an electrical connecting apparatus comprises a
support board having an upper surface and a lower surface, a block
having an attachment surface directing downward and attached to the
support board in a state where at least the attachment surface is
located below the support board, a flexible circuit board having a
contactor area in which a plurality of contactors are arranged and
an outside area around the contactor area and attached at part of
the outside area to the lower surface of the support board in a
state where at least the contactor area is opposed to the
attachment surface of the block, and a reference mark member having
a lower end surface and a reference mark for positioning provided
on the lower end surface and attached to the block in a state where
the lower end surface is exposed to the lower side of the circuit
board. Accordingly, the measurement accuracy of the probe tip
position is heightened.
Inventors: |
Hamada; Kazuhito (Aomori,
JP), Akiniwa; Takashi (Aomori, JP), Narita;
Satoshi (Aomori, JP) |
Assignee: |
Kabushiki Kaisha Nihon
Micronics (Tokyo, JP)
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Family
ID: |
38581090 |
Appl.
No.: |
12/296,430 |
Filed: |
March 22, 2007 |
PCT
Filed: |
March 22, 2007 |
PCT No.: |
PCT/JP2007/056751 |
371(c)(1),(2),(4) Date: |
October 07, 2008 |
PCT
Pub. No.: |
WO2007/116795 |
PCT
Pub. Date: |
October 18, 2007 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20100029099 A1 |
Feb 4, 2010 |
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Foreign Application Priority Data
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Apr 7, 2006 [JP] |
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2006-105924 |
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Current U.S.
Class: |
439/482;
324/750.16; 324/763.01 |
Current CPC
Class: |
G01R
1/0735 (20130101) |
Current International
Class: |
H01R
11/18 (20060101) |
Field of
Search: |
;439/482
;324/758,754,756,762 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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08-327658 |
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Dec 1996 |
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JP |
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10-505162 |
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May 1998 |
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JP |
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11-044708 |
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Feb 1999 |
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JP |
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2000-150594 |
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May 2000 |
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JP |
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2001-147240 |
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May 2001 |
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JP |
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2002-509604 |
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Mar 2002 |
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JP |
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2002-311049 |
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Oct 2002 |
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JP |
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2002-340932 |
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Nov 2002 |
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JP |
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2002-365310 |
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2003-043064 |
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Feb 2003 |
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2003-121469 |
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Apr 2003 |
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JP |
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2003-227849 |
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Aug 2003 |
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JP |
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2005-038983 |
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Feb 2005 |
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JP |
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9607924 |
|
Mar 1996 |
|
WO |
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9743653 |
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Nov 1997 |
|
WO |
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2007119636 |
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Oct 2007 |
|
WO |
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2007119637 |
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Oct 2007 |
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WO |
|
2007119638 |
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Oct 2007 |
|
WO |
|
2008038468 |
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Apr 2008 |
|
WO |
|
Other References
International Search Report for International Patent Application
Serial No. PCT/JP2007/065787; Japanese Patent Office, Oct. 30,
2007. cited by other .
International Search Report for International Patent Application
Serial No. PCT/JP2007/056751; Japanese Patent Office, Jun. 26,
2007. cited by other .
International Search Report for International Patent Application
Serial No. PCT/JP2007/057358; Japanese Patent Office, Jun. 12,
2007. cited by other .
International Search Report for International Patent Application
Serial No. PCT/JP2007/057359; Japanese Patent Office, Jun. 26,
2007. cited by other .
International Search Report for International Patent Application
Serial No. PCT/JP2007/057362; Japanese Patent Office, Jun. 12,
2007. cited by other.
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Primary Examiner: Chung Trans; Xuong M
Attorney, Agent or Firm: Santarelli; Bryan A. Graybeal
Jackson LLP
Claims
The invention claimed is:
1. An electrical connecting apparatus comprising: a support board
having an upper surface and a lower surface; a block having an
attachment surface directing downward and attached to said support
board in a state where at least said attachment surface is located
below said support board; a flexible circuit board having a
contactor area in which a plurality of contactors are arranged on
its lower surface thereof and an outside area around said contactor
area and attached at part of said outside area to the lower surface
of said support board in a state where at least said contactor area
is opposed to said attachment surface of said block; and a
reference mark member having a lower end surface and a reference
mark for positioning provided on said lower end surface and
attached to said block in a state where said lower end surface is
exposed to the lower side of said circuit board.
2. The electrical connecting apparatus according to claim 1,
wherein at least the lower end portion of said reference mark
member penetrates said circuit board.
3. The electrical connecting apparatus according to claim 2,
wherein said circuit board has a plurality of wires extending from
said contactor area radially outward.
4. The electrical connecting apparatus according to claim 1,
comprising at least a pair of said reference mark members whose
said lower end surfaces are distanced with said contactor area of
said circuit board in between.
5. The electrical connecting apparatus according to claim 1,
wherein said reference mark member includes a pin member.
6. The electrical connecting apparatus according to claim 5,
wherein said pin member is attached to said block at its upper
portion and is protruded below said circuit board at the lower end
portion.
7. The electrical connecting apparatus according to claim 1,
wherein said outer peripheral area of said circuit board has an
intermediate area around said contactor area and a plurality of
extending portions extending from said intermediate area in the
radial direction to be spaced around said intermediate area,
wherein said block has a truncated polygonal pyramidal downward
surface formed by said attachment surface, an intermediate surface
continuing into the perimeter of said attachment surface, and
slopes continuing into the perimeter of said intermediate surface,
wherein said contactor area is opposed to said attachment surface,
said intermediate area is opposed to a surface area around said
attachment surface, and at least parts of said extending portions
are opposed to said slopes, and wherein said reference mark member
is protruded downward from said slope of said block and penetrates
said extending portion of said circuit board.
8. The electrical connecting apparatus according to claim 1,
wherein said contactor area is bonded to said attachment
surface.
9. The electrical connecting apparatus according to claim 1,
wherein the lower end surface of said reference mark member is set
back further upward than said contactor area.
Description
PRIORITY CLAIM
The present application is a national phase application filed
pursuant to 35 USC .sctn.371 of International Patent Application
Serial No. PCT/JP2007/056751, filed Mar. 22, 2007; which further
claims the benefit of Japanese Patent Application 2006-105924,
filed Apr. 7, 2006; all of the foregoing applications are
incorporated herein by reference in their entireties.
CROSS REFERENCE TO RELATED APPLICATIONS
This application is related to U.S. application Ser. No. 12/297,214
entitled FLEXIBLE WIRING BOARD AND ELECTRICAL CONNECTING APPARATUS,
filed Oct. 14, 2008 and application Ser. No. 12/297,215 entitled
PROBE SHEET AND ELECTRICAL CONNECTING APPARATUS, filed Oct. 14,
2008 and application Ser. No. 12/297,216 entitled METHOD FOR
MANUFACTURING PROBE SHEET, filed Oct. 14, 2008, and U.S.
application Ser. No. 12/443,462 entitled ELECTRICAL CONNECTING
APPARATUS, filed Mar. 27, 2009.
TECHNICAL FIELD
An embodiment of the present invention relates to an electrical
connecting apparatus for use in an electrical test of a
flat-plate-shaped device under test such as an integrated circuit
or a display board.
BACKGROUND
A flat-plate-shaped device under test such as an integrated circuit
or a display board undergoes an electrical test with use of an
electrical connecting apparatus such as a probe card. In the
electrical test, the device under test with its electrodes
contacting the contactors of the electrical connecting apparatus
and is powered in that state.
As one of the electrical connecting apparatuses of this kind, there
is an art of using a flexible circuit board having a flexible
sheet-like member such as an FPC provided with a flexible
electrical insulating sheet and a plurality of wires formed on the
sheet, and contactors soldered to the respective wires of this
sheet-like member.
Referring to: Japanese Patent Appln Public Disclosure No
2002-311049, which is incorporated by reference, each contactor
comprises a pedestal portion coupled with the wire at one end
portion, an arm portion extending from the other end of the
pedestal portion in the longitudinal direction of the wire, and a
probe tip portion protruded from the tip end of the arm portion to
a side opposite the pedestal portion. The arm portion and the probe
tip portion act as a main body portion that is elastically deformed
substantially at the arm portion when the tip end of the probe tip
portion, that is, the probe tip, is thrust to an electrode of a
device under test.
The circuit board using such contactors is attached to a support
board such as a wiring board by an attachment apparatus so that the
probe tip portions can be directed to the device under test, thus
to be assembled into an electrical connecting apparatus.
The attachment apparatus comprises a first reinforcing plate
(plate-shaped member) arranged on the upper surface of the wiring
board, a ring-shaped second reinforcing plate (ring-shaped member)
arranged in a downward step portion provided at the center of the
wiring board so as to be located at the step portion, a plate
spring screwed on the lower side of the second reinforcing plate,
and a table (block) having at least an attachment surface on the
lower side and screwed on the lower side of the plate spring in a
state where the attachment surface is protruded downward of the
support board.
The first reinforcing plate is attached to the wiring board by a
plurality of attachment screws penetrating the first reinforcing
plate and the wiring board in the up-down direction and screwed in
the second reinforcing plate and attaches the second reinforcing
plate to the wiring board.
The aforementioned circuit board is bonded to the attachment
surface of the table at a contactor area at which the contactors
are arranged and is attached to the lower surface of the wiring
board by a ring-shaped pressing plate and a plurality of locking
screws at an outermost circumferential portion of an outer area
surrounding this contactor area.
The above electrical connecting apparatus undergoes positioning
(that is, alignment) in which the probe tips of the contactors are
positioned relative to the coordinates of a testing apparatus such
as a prober in a state of being attached to the testing apparatus.
Thereafter, the electrical connecting apparatus is powered at an
appropriate contactor in a state where the probe tip is thrust
against the electrode of the device under test. By doing so, an
electrical test is conducted.
The above positioning is performed generally by measuring the
position of the probe tip of the appropriate contactor relative to
the coordinates of the testing apparatus and thereafter changing
the coordinates on the software of the testing apparatus or
correcting the attachment position of the electrical connecting
apparatus to the testing apparatus so that the measured position
may be at an intended position on the coordinates of the testing
apparatus. Such positioning is performed every time the electrical
connecting apparatus is replaced.
Generally, as for the above electrical connecting apparatus, a
check as to whether or not the powering state is good is performed
on the side of a manufacturer of the electrical connecting
apparatus before the electrical connecting apparatus is delivered
from the manufacturer to the user. This check is performed by
powering all the probes simultaneously or sequentially, or per
plural probes in a state where the probe tips of all the contactors
are thrust against a pseudo test piece.
Accordingly, in the conventional electrical connecting apparatus,
even if the probe tip portion is cleaned after the check, foreign
matters such as scrapes generated at the time of the check
inevitably remain at the probe tip. Consequently, at the time of
positioning on the user side, the foreign matters remaining at the
probe tip lowers the measurement accuracy of the probe tip
position, and accurate positioning is difficult.
Also, the above probe tip position is generally determined by
directing light beam such as laser beam toward the probe tip and
measuring reflected light from the probe tip by a measuring
instrument or by capturing the probe tip by a video camera and
performing electrical image processing to the output signals from
the video camera.
However, since light from the vicinity of the probe tip is also
incident in the video camera, it is difficult to electrically
distinguish between light signals from the probe tip and light
signals from the vicinity of the probe tip. Thus, this also lowers
the measurement accuracy of the probe tip position, and accurate
positioning is difficult.
SUMMARY
An embodiment of the present invention heightens the measurement
accuracy of a probe tip position.
An electrical connecting apparatus according to an embodiment of
the present invention comprises a support board having an upper
surface and a lower surface, a block having an attachment surface
directing downward and attached to the support board in a state
where at least the attachment surface is located further to a lower
side than the support board, a flexible circuit board having a
contactor area in which a plurality of contactors are arranged and
an outside area around the contactor area and attached at part of
the outside area to the lower surface of the support board in a
state where at least the contactor area is opposed to the
attachment surface of the block, and a reference mark member having
a lower end surface and a reference mark for positioning provided
on the lower end surface and attached to the block in a state where
the lower end surface is exposed to the lower side of the circuit
board.
According to an embodiment, the position of the reference mark is
measured for positioning of the probe tips of the contactors
against a testing apparatus. At the time of this measurement, since
the reference mark is formed on the lower end surface of the
reference mark member other than the contactors, the reference mark
may have different optical characteristics from those of the
periphery such as a cross, a point, etc. Thus, the probe tip
positions can be measured highly accurately regardless of whether
or not foreign matters remain on the probe tips and without being
influenced by optical characteristics in the vicinity of the
mark.
At least the lower end portion of the reference mark member may
penetrate the circuit board. By doing so, since the reference mark
is exposed to the lower side of the circuit board, measurement of
the reference mark can be performed more reliably.
The circuit board may have a plurality of wires extending from the
contactor area outward in the radial direction. By doing so, the
interval of the wires adjacent to each other in the circumferential
direction can be wider at a position further outside in the radial
direction. Thus, the position that the reference mark member
penetrates can be a position outside the contactor area of the
circuit board, in which the positioning mark member does not
influence the wires of the circuit board, that is, a position where
the interval between the wires adjacent to each other in the
circumferential direction is wide.
At least a pair of the reference mark members whose lower end
surfaces are distanced with the contactor area of the circuit board
in between may be included. Thus, by measuring the reference marks
of both the reference mark members, the two-dimensional positions
of the contactors on the coordinates in the testing apparatus can
be measured accurately.
The reference mark member may include a pin member. Also, each pin
member may be attached to the block at the upper portion and may be
protruded to the lower side of the circuit board at the lower end
portion.
The outside area of the circuit board may have an intermediate area
around the contactor area and a plurality of extending portions
extending from the intermediate area in the radial direction to be
spaced around the intermediate area, the block may have a truncated
polygonal pyramidal downward surface formed by the attachment
surface, an intermediate surface continuing into the perimeter of
the attachment surface, and slopes continuing into the perimeter of
the intermediate surface, the contactor area may be opposed to the
attachment surface, the intermediate area may be opposed to a
surface area around the attachment surface, at least parts of the
extending portions may be opposed to the slopes, and each reference
mark member may be protruded downward from the slope of the block
and penetrate the extending portion of the circuit board. By doing
so, since the lower end surface of the reference mark member is
exposed downward from the extending portion extending in an
inclined manner, light from the lower end surface of the reference
mark member can be distinguished from light from the extending
portion reliably.
The contactor area may be bonded to the attachment surface. By
doing so, since the contactor area is supported on the block in a
stable manner, the contactors are stable against the support
board.
The lower end surface of the reference mark member may be set back
further upward than the contactor area. By doing so, when the probe
tips are thrust toward and against a device under test, the lower
end surface of the positioning mark member can be located further
upward than the contactors so that the positioning mark member does
not contact the device under test.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded perspective view showing an embodiment of an
electrical connecting apparatus according to the present
invention.
FIG. 2 is a plan view of the electrical connecting apparatus shown
in FIG. 1.
FIG. 3 is a cross-sectional view obtained along the line 3-3 in
FIG. 2.
FIG. 4 is a bottom view of the electrical connecting apparatus
shown in FIG. 1.
FIG. 5 is a bottom view of the electrical connecting apparatus
shown in FIG. 1 in a state where a circuit board and pressure
plates have been removed.
FIG. 6 is an exploded perspective view showing an embodiment of a
ring-shaped member, a plate spring, and spring holders.
FIG. 7 is a perspective view showing an embodiment of a block.
FIG. 8 is a perspective view showing a state where the circuit
board has been attached to the block.
FIG. 9 is an enlarged bottom view of the contactor area of the
circuit board and its perimeter.
FIG. 10 is a plan view showing an embodiment of the circuit
board.
FIG. 11 is a cross-sectional view obtained along the line 11-11 in
FIG. 9
FIG. 12 is an enlarged cross-sectional view of the contactor area
of the circuit board and its perimeter.
FIG. 13 is an enlarged cross-sectional view showing an attachment
state of the circuit board to a support board.
DESCRIPTION OF THE SYMBOLS
10 electrical connecting apparatus 12 support board 14 plate-shaped
member 16 ring-shaped member 18 plate spring 20 block 22 circuit
board 24 reference mark member 26 adjustment screw 28 through hole
30 tester land 32 connection land 34 screw member 36 attachment
screw 38 center area of the plate spring 39 extending area of the
plate spring 40 circumferential area of the plate spring 42 spring
holder 44 screw member 46, 48 flat areas 50 attachment surface of
the block 51 intermediate surface of the block 52 slope of the
block 54 lower block portion 56 attached surface of the block 58
upper block portion 60 attachment plate 62 screw member 64 recess
of the block 66 groove of the block 70 sheet 70a, 70b, 70c sheet
members 72 conductive path 74 contactor 76 contactor area of the
circuit board 78 outside area of the circuit board 80 intermediate
area of the circuit board 82 extending portion of the circuit board
84 connection bump 86 plate 88 pedestal portion of the contactor
88a, 88b first and second seat portions 90 main body portion of the
contactor 90a arm portion 90b probe tip 92 adhesive 94 rubber ring
96 pressure ring 100 positioning pin 102 reference mark
DETAILED DESCRIPTION
In an embodiment of the present invention, in FIG. 1, the
left-right direction is referred to as a left-right direction or an
X direction, the front-back direction is referred to as a
front-back direction or a Y direction, and the up-down direction is
referred to as an up-down direction or a Z direction. However,
these directions differ depending on the posture in which a device
under test is arranged in a testing apparatus, that is, the posture
of the device under test arranged in the testing apparatus.
Accordingly, as for the above directions, the X direction and the Y
direction may be determined to be within any one plane of a
horizontal plane, an inclined surface inclined to the horizontal
plane, and a vertical plane vertical to the horizontal plane or may
be determined to be a combination of these planes in accordance
with an actual testing apparatus.
An electrical connecting apparatus 10 is used in an electrical test
of a rectangular integrated circuit (not shown) in a similar manner
as a probe card. The integrated circuit has a plurality of
electrodes. These electrodes are arrayed in two lines to be spaced
in the left-right direction (or the front-back direction) in the
example shown in FIG. 9.
Referring to FIGS. 1 to 13, the electrical connecting apparatus 10
includes a disk-shaped support board 12, a plate-shaped member 14
attached to the upper surface of the support board 12, a
plate-shaped ring-shaped member 16 arranged on the lower side of
the plate-shaped member 14, a plate spring 18 arranged on the lower
side of the ring-shaped member 16, a table or a block 20 attached
to the lower surface of the plate spring 18, a film-shaped board or
a circuit board 22 arranged on the lower side of the block 20, a
plurality of reference mark members 24 attached to the block 20,
and a plurality of adjustment screws 26 (refer to FIGS. 2 and 3)
penetrating the plate-shaped member 14 in its thickness direction
and abutting to the aforementioned ring-shaped member 16.
The support board 12 has a through hole 28 passing through its
center in the thickness direction (up-down direction), has a
plurality of tester lands 30 (refer to FIG. 2) connected to a
tester at the circumferential portion on the upper surface, and has
a plurality of connection lands 32 (refer to FIGS. 5 and 13) on the
lower surface in an area between the through hole 28 and the
circumferential portion to be spaced in the circumferential
direction. The through hole 28 has a circular flat surface
shape.
The support board 12 also has inside a plurality of wires
(conductive paths) respectively connecting the tester lands 30 and
the connection lands 32 in one-to-one relationship. Such a support
board 12 may be a wiring board made of epoxy resin containing glass
or a ceramic material.
The plate-shaped member 14 is formed in a larger disk shape than
the through hole 28 and is attached to the upper surface of the
support board 12 by a plurality of screw members 34 penetrating the
plate-shaped member 14 and screwed in the support board 12 in a
state of closing the through hole 28, that is, in parallel with the
support board 12.
The plate-shaped member 14 is made of a metal material such as
stainless steel so as to act as a reinforcing plate for the support
board 12. Thus, the plate-shaped member 14 does not need to be a
complete plate, but may be one formed in a plate shape consisting
of a flat center portion, a plurality of extending portions
extending from this center portion in the radial direction of a
virtual circle to be spaced in the circumferential direction of the
virtual circle, and an outer portion connected to the tip ends of
these extending portions and extending in the circumferential
direction of the virtual circle, as the plate spring 18 described
later.
As shown in FIG. 6, the ring-shaped member 16 is also formed in a
plate-shaped ring shape made of a metal material such as stainless
steel, especially a metal material having a small thermal expansion
coefficient, and having a slightly smaller outer dimension than the
diameter dimension of the through hole 28, and is located in the
through hole of the support board 12.
The ring-shaped member 16 is attached to the lower surface of the
plate-shaped member 14 in parallel with the support board 12 and
the plate-shaped member 14 by a plurality of attachment screws 36
penetrating the plate-shaped member 14 in its thickness direction
and screwed in the ring-shaped member 16.
As shown in FIG. 6, the plate spring 18 has a flat center area 38,
a plurality of plate-shaped extending areas 39 extending from the
center area 38 in the radial direction of a virtual circle to be
spaced in the circumferential direction of the virtual circle, and
a ring-shaped circumferential area 40 integrally continuing around
the extending areas 39.
The center area 38 and the plate-shaped extending areas 39 are
formed in a star (*) shape. The number of the rim areas 39 may be
an appropriate value such as four, six, eight, or the like. In the
example shown in the figures, the number of the extending areas 39
is four, and thus the center area 38 and the extending areas 39
form a cross shape crossing at the center area 38.
The plate spring 18 may be made of a material selected from a group
including tungsten, molybdenum, their alloy, and a ceramic
material, having a smaller thermal expansion coefficient than that
of stainless steel.
The thickness dimension of the plate spring 18 may be approximately
0.1 mm to 0.25 mm. The stiffness of the plate spring itself may
become too big when the thickness dimension of the plate spring 18
exceeds 0.1 mm, while the flexibility of the plate spring itself
becomes too small when it is less than 0.25 mm. Thus, when the
thickness dimension of the plate spring 18 is within the above
range, the flexibility amount of the plate spring 18 by overdrive
described later becomes an optimal value, and irregular flexibility
of the plate spring 18 is prevented.
The plate spring 18 is attached to the circumferential area 40 to
the lower surface of the ring-shaped member 16 in parallel with the
support board 12 by a plurality of arc-shaped spring holders
respectively formed in arc shapes and a plurality of screw members
44 penetrating the spring holders 42 from the lower side and
screwed in the ring-shaped member 16
In the example shown in the figures, the spring holders 42 are
combined with each other to form a similar ring at the
circumferential area 40 of the plate spring 18. However, a single
ring-shaped spring holder is also applicable.
As shown in FIG. 6, as for the internal circumferential surfaces of
the ring-shaped member 16 and the spring holders 42, portions
corresponding to the boundaries between the extending areas 39 and
the circumferential area 40 of the plate spring 18 are respectively
flat areas 46 and 48 extending in the tangential direction of the
outer surface of the plate spring 18 and in the up-down
direction.
As shown in FIG. 7, the block 20 comprises a lower block portion 54
having a truncated polygonal pyramidal downward surface formed by
an attachment surface 50 to which the circuit board 22 is to be
attached, an intermediate surface 51 continuing into the perimeter
of the attachment surface 50, and a plurality of slopes 52
continuing into the perimeter of the intermediate surface 51 and a
prismatic upper block portion 58 whose upper end surface is an
attached surface 56 to the plate spring 18
In the example shown in the figures, the attachment surface 50, the
intermediate surface 51, and the attached surface 56 are parallel
surfaces, and the downward surface of the lower block portion 54 is
formed in a truncated octagonal pyramidal shape.
The block 20 is attached to the lower surface of the center area 38
of the plate spring 18 at the upper block portion 58 by a plurality
of screw members 62 in a state where the center area 38 of the
plate spring 18 is sandwiched between a rectangular attachment
plate 60 (ref. to FIGS. 1 and 3) and the upper block portion 58 and
in a state where the lower block portion 54 is protruded in the
downward direction of the support board 12. The attachment surface
50 of the block 20 is in a rectangular shape similar to the shape
of an integrated circuit to be tested.
As shown in FIGS. 11 and 12, as for the lower end portion of the
lower block portion 54, the attachment surface 50 is slightly
protruded downward more than the intermediate surface 51 around it.
At the lower end portion of the lower block portion 54 are formed a
recess 64 opened at the attachment surface 50 and a downward groove
66 extending around the recess 64.
As shown in FIGS. 8 to 13, the circuit board 22 comprises an
electrical insulating sheet 70 such as polyimide, a plurality of
strip-like wires or conductive paths 72 formed inside the sheet 70,
and a plurality of contactors 74, each contactor 74 being equipped
with the conductive path 72. Thus, the circuit board 22 has
flexibility. The sheet 70 is constituted by three sheet members
70a, 70b, and 70c.
The circuit board 22 has a rectangular contactor area 76 in which
the contactors 74 are arranged and an outside area 78 around the
contactor area 76. The outside area 78 comprises an intermediate
area 80 integrally continuing into the perimeter of the contactor
area 76 and a plurality of extending portions 82 extending from the
intermediate area 80 in the radial direction of a virtual circle
centering around the contactor area 76 to be spaced around the
intermediate area 80.
Each conductive path 72 extends from the inside of the contactor
area 76 in which the contactors 74 are arranged to the outside area
78 outward in the radial direction of the aforementioned virtual
circle. At the outside end portion of each conductive path 72 are
provided connection bumps 84 (refer to FIG. 13) penetrating the
sheet members 70b, and 70c and protruded upward. In the example
shown in the figures, each conductive path 72 is in a three-layered
structure of copper, nickel, and copper.
As shown in FIGS. 11 and 12, a plate 86 is buried in a position
corresponding to the contactor area 76 so as to maintain parallel
accuracy of the contactor area 76. Accordingly, the contactor area
76 is protruded downward from the intermediate surface 51 as much
as the sum of the thickness of the plate 86 and the amount of
protrusion of the attachment surface 50 relative to the
intermediate surface 51. The plate 86 is made of an appropriate
material such as a ceramic plate, a stainless steel plate, or the
like.
The sheet members 70a and 70b cooperatively sandwich the conductive
paths 72 there between, and the sheet members 70b and 70c
cooperatively envelop the plate 86 therein.
The above sheet 70, conductive paths 72, and plate 86 can be
manufactured with use of a photolithographic technique, an
electroplating technique, a resin application technique, an
electroforming technique, etc. by forming a plurality of conductive
paths 72 on one surface of the sheet member 70a, subsequently
forming the sheet member 70b on a conductive paths 72 side of the
sheet member 70a, arranging the plate 86 on a position of the sheet
member 70b corresponding to the contactor area 76, and forming the
sheet member 70c on the plate side of the sheet member 70b.
Each contactor 74 includes a pedestal portion 88 joined to a
corresponding conductive path 72 and protruded in the downward
direction of the sheet member 70a and a main body portion 90
integrally continuing into the lower end of the pedestal portion
88
The pedestal portion 88 comprises a first seat portion 88a made of
a metal material of the same kind (e.g., copper) as that of the
junction portion of the corresponding conductive path 72 and a
second seat portion 88b joined to the lower end of the first seat
portion 88a.
The first seat portion 88a is joined to the corresponding
conductive path 72 at its rear end surface. The second seat portion
88b may be made of the same metal material (e.g., nickel) as that
of the main body portion 90 integrally with the main body portion
90
The main body portion 90 comprises an arm portion 90a extending
horizontally from the lower end of the second seat portion 88b and
a probe tip 90b protruded downward from the tip end of the arm
portion 90a.
The above contactor 74 may be manufactured with use of a
photolithographic technique, an electroplating technique, an
electroforming technique, etc. by sequentially forming the first
seat portion 88a, the second seat portion 88b, the arm portion 90a,
and the probe tip 90b in this order or reverse order.
After a part of the sheet member 70a is removed, the contactor 74
manufactured as above is joined to the corresponding conductive
path 72 at the upper end surface of the first seat portion 88a by
conductive adhesive. Thus, each contactor 74 is supported on the
sheet 70 in a cantilevered manner in a state where the main body
portion 90 is distanced downward from the sheet 70.
However, the sheet 70, the conductive paths 72, and the contactors
74 may be manufactured consecutively with use of a
photolithographic technique, an electroplating technique, a resin
application technique, an electroforming technique, etc. By doing
so as well, each contactor is supported on the sheet 70 in a
cantilevered manner.
In the above case, they may be manufactured in order of the probe
tips 90b, the arm portions 90a, the second seat portions 88b, the
sheet member 70a, the first seat portions 88a, the conductive paths
72, the sheet member 70b, and the sheet member 70c. The plate 86
only needs to be arranged on the sheet member 70b prior to
formation of the sheet member 70c.
If the circuit board 22 is manufactured as above, the respective
coupling strengths between the conductive path 72 and the first
seat portion 88a, between the first seat portion 88a and the second
seat portion 88b, between the second seat portion 88b and the arm
portion 90a, and between the arm portion 90a and the probe tip 90b
are increased.
Also, when the first seat portion 88a is made of the same metal
material as the junction portion of the conductive path 72, and the
second seat portion 88b is the same metal material as the main body
portion 90, the coupling strengths between the first seat portion
88a and the conductive path 72 and between the second seat portion
88b and the main body portion 90 are further increased.
The junction surface between the first and second seat portions 88a
and 88b is within the sheet member 70a as shown in FIG. 12.
Accordingly, since the junction surface between both the seat
portions 88a and 88b is closed in the sheet member 70a, even when a
bending moment acts on the pedestal portion 88, separation of the
first and second seat portions 88a and 88b caused by the bending
moment is prevented.
As shown in FIGS. 11 and 12, the circuit board 22 is bonded to the
attachment surface 50 at least contactor area 76 by adhesive 92
stored in the recess 64 in a state where the contactor area 76 and
the intermediate area 80 are opposed to the attachment surface 50,
and where part of each extending portion 82 is opposed to each
slope 52.
The contactor area 76 and the intermediate area 80 around it are
respectively thrust to the attachment surface 50 and the
intermediate surface 51 around it at the time of being bonded to
the block 20. Thus, since excessive adhesive in the recess 64 is
pushed out to an area around the contactor area 76 (at least part
of the intermediate area 80), the circuit board 22 is also bonded
to an area around the attachment surface 50 (at least part of the
intermediate surface 51) at the area around the contactor area 76
as well. As a result, the circuit board 22 is maintained in a state
where the contactor area 76 is protruded further downward than a
portion around it as shown in FIG. 12.
When the contactor area 76 and the area around it are bonded to the
attachment surface 50 and the area around it as above, the
contactor area 76 and the area around it are supported on the block
20 in a stable manner, and thus the contactors 74 are stable
against the support board 12.
The circuit board 22 is also attached to the lower surface of the
support board 12 by an elastic plate-shaped rubber ring 94 such as
a silicon rubber, a plate-shaped pressure ring 96 having certain
hardness such as stainless steel, and a plurality of screw members
98 in a state where the connection bumps 84 are thrust to the
connection lands 32 as shown in FIG. 13.
Positioning of the circuit board 22 relative to the support board
12 is performed by a plurality of positioning pins 100 (ref. to
FIG. 3) extending downward from the support board 12 and
penetrating the circuit board 22, the rubber ring 94, and the
pressure ring 96 to be protruded downward. Each positioning pin 100
is held in the support board 12 in a stable manner.
In a state where the circuit board 22 is attached to the block 20
and the support board 12 as above, each contactor 74 is aligned so
that its probe tip 90b is opposed to a corresponding electrode of a
device under test and is electrically connected to the tester land
30 of the support board 12 via the conductive path 72, the
connection bumps 84, the connection lands 32, the wires in the
support board 12, etc.
Each reference mark member 24 is a pin member protruded downward
from the slope 52 of the lower block portion 54 and is supported in
the lower block portion 54 at its upper portion in a stable manner.
In the example shown in the figures, three pairs of reference mark
members 24 are provided. The reference mark members 24 of each pair
are opposed to each other with the contactor area 76 and the
intermediate area 80 in between.
The lower end surface of each reference mark member 24 is a surface
parallel to the attachment surface 50, and the height position of
the lower end surface of each reference mark member 24 is set back
further upward than the height position of the contactors 74.
The lower portion of each reference mark member 24 is protruded
downward of the circuit board 22 at the extending portion 82 of the
circuit board 22, passing between the adjacent conductive paths 72.
Since the interval of the adjacent conductive paths 72 at the
extending portion 82 is wider than that at the intermediate area
80, the reference mark member 24 does not influence the formation
position of the conductive paths 72.
As shown in FIG. 9, each reference mark member 24 has a reference
mark 102 on the lower end surface. Each reference mark 102
cooperates with a reference mark 102 of an opposed reference mark
member 24 with the contactor area 76 in between to represent the
positions of the probe tips 90b located between both the reference
marks 102 in the electrical connecting apparatus 10.
Each reference mark 102 has different optical characteristics from
those of the periphery. Although the reference mark 102 is a round
mark at the center in the example shown in the figures, it may be a
dot, a crosshair intersection, etc.
Each reference mark 102 can be formed by forming a mark layer on
the lower surface of the reference mark member 24 in advance by an
appropriate technique such as electroplating or paint application,
and after completion of the electrical connecting apparatus 10, by
measuring the positions of the probe tips 90b, and removing by
laser beam corresponding positions in the mark layer based on the
measurement result. By doing so, the reference mark 102 can be
formed accurately without depending on the assembling accuracy of
the electrical connecting apparatus 10
The block 20, the reference mark members 24, the spring holders 42,
the attachment plate 60, and the positioning pins 100 are made of
appropriate materials, for example electrical insulating metal
materials.
In a state where the electrical connecting apparatus 10 is
assembled as above, parallel accuracy of the contactor area 76
relative to the support board 12 is adjusted.
This parallel accuracy adjustment may be performed by adjusting the
screwing amount of the adjustment screws 26 in the plate-shaped
member 14 so that the contactor area 76 may become parallel to the
support board 12 in a state where the screwing amount of the
attachment screws 36 in the ring-shaped member 16 is small and
thereafter screwing the attachment screws 36 in the ring-shaped
member 16 to reach a state where the adjustment screws 26 abut on
the upper surface of the ring-shaped member 16. Accordingly,
parallel accuracy of the contactor area 76 relative to the support
board 12 may be adjusted easily.
Since the contactor area 76 is bonded to the attachment surface 50,
it is reliably displaced together with the block 20 relative to the
support board 12 at the time of the aforementioned parallel
accuracy adjustment.
The electrical connecting apparatus 10 is incorporated in the
testing apparatus in a state where the contactor area 76 is above
the arrangement area of the device under test, and where the probe
tip 90b of each contactor 74 is opposed to an electrode of the
device under test, and the tester lands 30 of the support board 12
are connected to electrical circuits for an electrical test. In
this manner, each contactor 74 is electrically connected to the
electrical circuits for the electrical test.
In the electrical connecting apparatus 10, the reference marks 102
are measured for positioning of the probe tips 90b of the
contactors 74 relative to the testing apparatus in a state where
the electrical connecting apparatus 10 is mounted on the testing
apparatus.
At the time of this measurement, since the reference marks 102 are
formed on the lower end surfaces of the reference mark members 24
other than the contactors 74, the probe tip positions may be
measured highly accurately and reliably regardless of whether or
not foreign matters remain on the probe tips 90b and without being
influenced by optical characteristics in the vicinity of the
reference marks 102.
As for the reference marks 102, only the reference marks 102 of at
least one pair of reference mark members 24 whose lower end
surfaces are distanced with the contactor area 76 in between need
to be measured. Accordingly, the two-dimensional positions of the
contactors 74 on the coordinates in the testing apparatus may be
measured accurately.
However, if the reference marks 102 of the three pairs of reference
mark members 24 whose lower end surfaces are distanced with the
contactor area 76 in between are measured, the two-dimensional
positions of the contactors 74 on the coordinates in the testing
apparatus may be measured more accurately.
At the time of the electrical test, the electrical connecting
apparatus 10 and the device under test are moved relatively in
directions in to approach each other. By doing so, the probe tip
90b of each contactor 74 is thrust to a corresponding electrode of
the device under test, and an overdrive acts on the contactor
74.
When the probe tip 90b of each contactor 74 is thrust to the
electrode of the device under test, the cantilevered contactor 74
is elastically deformed slightly in an arc shape at the arm portion
90a, and the plate spring 18 is elastically deformed due to the
overdriving.
When the overdriving acts on the contactor 74, the electrical
connecting apparatus 10 has the following technical merits.
Since the contactor area 76, the intermediate area 80, and part of
each extending portion 82 of the circuit board 22 are opposed to
the attachment surface 50, the intermediate surface 51, and a slope
52 of the block 20, respectively, and moreover the height position
of the lower end surface of each reference mark member 24 is higher
than the height position of the contactors 74, the reference mark
member 24 does not contact the device under test when the probe
tips 90b are thrust to the electrodes of the device under test.
When the contactors 74 are thrust to the electrodes, the plate
spring 18 acts as a reaction force body for the center area of the
circuit board 22, which is the arrangement area of the contactors
74. Consequently, the plate spring 18 is elastically deformed
slightly by the circuit board 22 and the block 20 and allows the
contactor area 76 to be displaced upward in parallel by the
overdrive. This leads to a uniform pressure force of the contactors
74 to the electrodes.
The block 20 reliably transmits the deformation of the contactor
area 76 of the circuit board 22 to the plate spring 18, and the
through hole 28 allows the plate spring 18 to be elastically
deformed easily to the ring-shaped member 16 side. This stabilizes
the elastic deformation of the plate spring 18 and the circuit
board 22 and facilitates contact of each contactor 74 with the
electrode.
Irregular flexibility of the plate spring 18 when the overdrive
acts on the contactors 74 is reliably prevented by the fact that
the block 20 is attached to the star-shaped or cross-shaped
intersection of the plate spring 18 and the fact that the inner
peripheral surfaces of the ring-shaped member 16 and the spring
holders 42 have the flat areas 46 and 48 extending in the
tangential direction and in the up-down direction of the outer
peripheral surface of the plate spring 18 at the respective
portions corresponding to the boundaries between the extending area
39 and the circumferential area 40 of the plate spring 18, and the
thrusting force of the contactors 74 to the electrodes is more
uniform.
Since the coupling portion between both the seat portions 88a and
88b is located within the sheet 70, that is, the coupling portion
is located within the thickness dimension of the sheet 70, part of
the bending moment acting on the pedestal portion 88 is received in
the sheet 70, and the coupling portion is protected by the sheet
70. As a result, separation of the contactor from the sheet 70
caused by the overdrive prevented while the coupling force between
the conductive path 72 and the pedestal portion 88 is large.
The pedestal portion 88 distances the main body portion 90,
particularly the tip end of the contactor 74, from the sheet 70
significantly. Accordingly, the overdrive makes it difficult for
the main body portion 90 to contact the sheet 70, and for the sheet
70 to contact the device under test, as a result of which the
contactor 74 reliably contacts the electrode of the device under
test.
When the plate spring 18 made of a material having a smaller
thermal expansion coefficient than that of stainless steel is used,
thermal expansion and contraction of the plate spring 18 and
displacement of the probe tip positions in reaction to heating or
cooling of the device under test are small. Consequently, breakage
of the probe tips and contact failure of the probe tips with the
electrodes of the device under test may be prevented.
When the plate spring 18 has a thickness dimension of 0.1 mm to
0.25 mm, the flexibility amount of the plate spring 18 by the
overdrive may be an optimal value, and irregular flexibility of the
plate spring 18 is prevented more reliably.
When the plate spring 18 and the contactor 74 are designed so that
the flexibility amount of the plate spring 18 when the overdrive
acts on the contactor may become twice as much as that of the
contactor 74, the flexibility amounts of the plate spring 18 and
the contactor 74 by the overdrive may be optimal values, and
irregular flexibility of the plate spring 18 or the contactor 74
may be prevented.
The present invention is not limited to the above embodiments but
may be altered in various ways without departing from the spirit
and scope of this description.
* * * * *